Electron transfer reactions are critical steps in a wide variety of biological interactions ranging from photosynthesis to aerobic respiration. Studies of electron transfer reactions in both chemical and biological systems have yielded a large body of knowledge and a strong theoretical base, which describes the rate of electron transfer in terms of a small number of parameters.
With this knowledge, an electroactive moiety (EAM) may be designed as a sensing molecule. The magnitude of electron transfer is changed upon its interaction with a target.